David actually said HE was the Sheriff in 317 when he’s reassuring MM about giving Henry a driving lesson. So I think he assumed that post (again) when Emma wasn’t there after they came back. Maybe they have two sheriffs? He did act as acting sheriff when she was in the EF with MM in S2, too.
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Keeper of Belle's Gold magic, sand dollar, cloaks, purple FTL outfit, spell scroll, library key, copy of Romeo and Juliet, and cry-muffling pillow, Rumple's doll, overcoat, and strength, and The Timeline. My spreadsheet: https://drive.google.com/file/d/0B6r8CySCCWd9R0RUNm4xR3RhMEU/view?usp=sharing